Allen-Bradley 440R-S13R2 — Guardmaster CI Safety Relay Review

By Abdullah Zahid
16 min read
Allen-Bradley 440R-S13R2 Guardmaster CI Safety Relay 24VDC mounted on DIN rail in industrial control panel

Allen-Bradley 440R-S13R2 Guardmaster CI Safety Relay: Specs, Pricing and Alternatives

Controls engineers specifying safety hardware for 24 VDC machines often land on the Allen-Bradley 440R-S13R2 after working through a risk assessment that demands a flexible single-input safety relay with multiple redundant safety outputs. The 440R-S13R2 is the Guardmaster CI Safety Relay in Bulletin 440R — a configurable-input device that accepts N/C dry contacts, OSSD outputs, and selected solid-state safety sensors on a single input channel, then switches three normally open safety contacts plus one solid-state auxiliary output. If you have confirmed this is the part your system requires, check current pricing and availability at LeadTime.ca — we ship worldwide.

Who Should Buy the 440R-S13R2 — and Who Shouldn't

The Allen-Bradley 440R-S13R2 is the right relay for controls engineers and OEM machine builders who are already working within a Rockwell Automation or Guardmaster GSR safety architecture and need a single, configurable input channel that can handle mixed safety device types without rewiring the cabinet for each application.

  • Your control supply is 24 VDC — this relay has no 24 VAC or 120 VAC variant under this catalog number.
  • You need exactly three normally open safety output contacts to de-energize contactors or final switching elements.
  • Your safety device is one of the supported input types: N/C contacts, OSSD-style sensor outputs, or compatible solid-state safety devices configurable via the relay's input selection method.
  • You require a single auxiliary solid-state output for PLC status feedback or indicator signaling.
  • Your panel uses DIN rail mounting and you can accommodate the relay's standard control cabinet form factor.
  • You may need to expand the safety circuit later using the single-wire safety connection feature to link additional Guardmaster GSR modules.

If your application requires multiple independent safety input channels in a single device, built-in off-delay timing, or complex logic across several safety zones, the CI variant is not the right fit. Consider the Guardmaster DI, DIS, or SI modules for dual-channel or specialized input configurations, or evaluate a modular safety controller for more complex architectures. Specific alternatives are discussed in the variant comparison section below.

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What the 440R-S13R2 Actually Does in a Safety Circuit

The 440R-S13R2 is a next-generation Guardmaster CI Safety Relay that sits between the field safety device and the machine's final switching elements. Its role is to monitor the state of the connected safety device — whether that is an emergency stop button, a safety gate interlock, an OSSD light curtain, or a safety mat — and to respond to any unsafe state by opening its three normally open safety output contacts, which in turn de-energize the contactors controlling hazardous motion or energy.

What sets the CI variant apart within the Guardmaster GSR family is its configurable single input. Rather than being hard-wired for one input type, the 440R-S13R2 can be set to match the device connected to it: contact-based safety devices, OSSD-output sensors, or selected solid-state safety devices. This flexibility makes it practical for machine builders who work with varied safety hardware across different projects without needing a separate relay model for each input type. The single-wire safety connection feature allows this relay to be linked to other GSR modules in the same cabinet, simplifying expansion wiring. An onboard solid-state auxiliary output provides a status signal that can be wired directly to a PLC input or an indicator lamp for diagnostics and event logging. LED indicators on the relay face give immediate local feedback on power status, input state, fault conditions, and output status — reducing troubleshooting time during commissioning and maintenance.

Four verified proof points anchor the specification claims here: the manufacturer describes the 440R-S13R2 as a CI relay with single-wire safety connection capability; official documentation confirms universal input compatibility across contact and OSSD device types when configured correctly; datasheets specify three normally open safety outputs plus one solid-state auxiliary output as the standard output configuration; and the Guardmaster Safety Relays user manual includes dedicated application examples specifically for the CI relay under catalog number 440R-S13R2, confirming its place in the core next-generation GSR lineup.

Typical Safety System Architecture

The 440R-S13R2 sits in the safety logic layer — downstream of the field safety device and upstream of the machine's final switching elements. Here is where it fits in the signal chain:

  • 24 VDC control power supply feeds the relay's power terminals, with appropriate upstream overcurrent protection in place.
  • A field safety device (emergency stop button, safety gate interlock switch, OSSD light curtain, or safety mat) connects to the relay's configurable single input channel.
  • The 440R-S13R2 evaluates the input state and controls its three normally open safety output contacts accordingly, opening them when the safety device signals an unsafe condition.
  • The three safety output contacts wire in series with contactor coils or other final switching devices that remove power from hazardous machine elements.
  • The solid-state auxiliary output connects to a PLC input or pilot indicator for status monitoring and diagnostics.
  • If additional safety zones are required, further Guardmaster GSR modules can be linked via the single-wire safety connection, avoiding complex multi-wire runs between relays.

Typical Applications and Deployment Scenarios

Emergency stop monitoring on small to mid-sized machines is the most direct use case. A single E-stop button or a series of E-stop buttons wired to the configurable input gives the relay all it needs to protect one or more contactors through its three safety outputs — a common requirement on packaging, conveyor, and assembly equipment.

Safety gate and guard door monitoring is another high-frequency application. Mechanical safety interlock switches or OSSD-output safety switches on hinged or sliding guards connect directly to the 440R-S13R2 input, with the relay holding the machine's drive or actuator contactors closed only when the guard is confirmed secured.

Light curtains, safety mats, and safety edges that produce OSSD outputs integrate cleanly with the CI input when configured for OSSD mode, making the 440R-S13R2 a practical choice on robotic cell perimeters, press guarding, and palletizer access points in discrete manufacturing environments.

For maintenance engineers tasked with upgrading legacy machines to meet current safety requirements, the 440R-S13R2 offers a path to higher safety integrity without requiring a full safety PLC retrofit. A single relay mounted on existing DIN rail, wired to an already-installed E-stop or gate switch, can significantly raise the safety performance of an older circuit.

Application Typical Deployment
Emergency stop monitoring Single or series E-stop buttons on packaging, conveyor, or assembly machines; three safety outputs to main contactor coils
Safety gate and guard door interlock Mechanical or OSSD-output safety interlock switches on hinged guards; relay controls drive or actuator contactors
Light curtain integration OSSD-output light curtains on robotic cell access or press guarding; CI input configured for OSSD mode
Safety mat and edge monitoring Pressure-sensitive safety mats or edges on palletizer or collaborative robot perimeters; configurable input matches device type
Legacy machine safety upgrade Retrofit onto existing DIN rail alongside original contactors; replaces or supplements older discrete safety circuit
Guardmaster GSR system expansion Linked to existing DI, DIS, or SI modules via single-wire safety connection to add a zone without full rewiring

Key Specifications for Purchase Decisions

Parameter Value / Description
Brand / Series Allen-Bradley Guardmaster, Bulletin 440R (CI)
Catalog Number 440R-S13R2
Supply Voltage 24 VDC
Safety Inputs 1 configurable input — supports N/C contacts, OSSD, and selected solid-state safety devices
Safety Outputs 3 normally open (NO) safety contacts
Auxiliary Output 1 solid-state status output
Mounting DIN rail
Certifications cULus, CE, and additional regional approvals — verify exact marks from current datasheet
Safety Standards Designed for systems evaluated per EN ISO 13849, IEC 62061, IEC 61508 — consult datasheet for exact ratings
External Protection Requires external overcurrent protection appropriate to load and wiring — no integrated circuit breaker

Full technical specifications are available on the product page at LeadTime.ca.

440R-S13R2 vs Other Guardmaster GSR Variants: Which One Do You Actually Need?

Model / Type Input Configuration Key Differentiator Best Fit Scenario
440R-S13R2 (CI) 1 configurable input (N/C, OSSD, solid-state) Universal configurable single input; single-wire safety connection Mixed or variable safety device types on one zone; flexible OEM applications
Guardmaster DI Dual-channel contact input Fixed dual N/C contact input for high-redundancy dry-contact devices E-stop or gate switch with two independent N/C contact channels required
Guardmaster DIS Dual-channel contact input with reset options DI function with additional manual/automatic reset flexibility Dual N/C contact input with specific reset behavior requirements
Guardmaster SI Single-channel contact input Fixed single N/C contact input; simpler configuration than CI Applications with only a single-channel N/C contact device and no need for input-type flexibility
Guardmaster GLP Input via safety gate locking Guard locking control integrated into relay function Trapped-key or solenoid-lock guard door applications
Guardmaster EM / EMD Expansion module Adds additional safety output contacts by expanding an existing GSR module When three safety outputs of the CI are insufficient and more switching capacity is needed
Modular safety controller Multiple configurable inputs Programmable logic, multiple zones, complex safety functions Multi-zone machines, complex interlocking, embedded timing, or high channel counts

If your application requires more than three safety outputs or you need to expand switching capacity without adding full safety relay modules, the Guardmaster EM or EMD expansion modules are the natural next step — check current availability of the 440R-S13R2 and related GSR modules at LeadTime.ca.

Expert Verdict: Is the 440R-S13R2 the Right Safety Relay for Your Machine?

The Allen-Bradley 440R-S13R2 earns its place on the BOM for controls engineers and OEM machine builders operating in Rockwell Automation environments where flexibility at the safety input matters. The configurable single input — covering N/C dry contacts, OSSD sensor outputs, and selected solid-state safety devices — means one catalog number can serve multiple machine variants without panel redesigns. Three normally open safety outputs give sufficient switching capacity for the majority of small to mid-sized 24 VDC machines: a main contactor, a secondary contactor, and a safety-rated downstream device, all de-energized in a single relay operation. The solid-state auxiliary output and LED diagnostics reduce commissioning time and simplify PLC-based fault logging. For teams already standardized on Guardmaster GSR hardware, the single-wire safety connection feature directly reduces wiring complexity when expanding circuits.

Where the 440R-S13R2 reaches its limits is equally important to state clearly. If your risk assessment calls for two independent safety input channels in a single module, the DI or DIS variants are the correct choice — the CI type provides one input channel, not two. If your application requires built-in off-delay timing, speed monitoring, or guard locking control, other members of the 440R GSR family address those functions directly. For machines with multiple independent safety zones, complex interlocking logic, or high channel counts, a modular safety controller will deliver better long-term value and easier validation than a chain of discrete relays. The 440R-S13R2 is an efficient, defensible choice precisely when the application is bounded: one zone, one configurable input, three output contacts, and a clear risk assessment that confirms those parameters are sufficient.

From a procurement standpoint, the 440R-S13R2 is an active catalog number in the core Guardmaster GSR lineup, and availability through Rockwell-authorized and specialist distributors is generally reliable with lead times ranging from immediate stock to several weeks depending on channel and order volume. Confirming live stock before a machine build deadline is always the right move — safety hardware delays have downstream consequences that go beyond budget. For verification that this is the correct CI module for your application and to confirm current lead time, view pricing and availability on the product page at LeadTime.ca.

For volume pricing or to confirm lead time before committing to a build, contact the LeadTime.ca team directly — we ship worldwide.

What Engineers Need to Know Before Ordering the 440R-S13R2

Community discussion specific to the 440R-S13R2 is limited in volume, but the broader Guardmaster GSR family generates consistent feedback across forums including PLCTalk, PLCS.net, MrPLC, Reddit's r/PLC and r/automation communities, and major distributor Q&A sections. The pattern is clear enough to act on when specifying this relay.

Engineers who work regularly with Guardmaster hardware tend to report that the GSR family integrates predictably into Rockwell-based control panels once the correct model is selected. Terminal labeling is described as clear and consistent, which simplifies panel documentation, maintenance records, and handover between engineering teams. The family-level consistency of the GSR line — shared wiring conventions, similar LED indicator behavior, and compatible single-wire safety connection across modules — reduces the learning curve when a technician who knows one GSR variant encounters another on the same machine. That consistency is a genuine operational advantage in facilities that run multiple machine types.

The recurring friction point is model selection before the order is placed, not the relay itself after it arrives. Discussions consistently flag confusion between the CI, DI, DIS, and SI designations as the source of ordering errors. A DI module ordered where a CI was required — or a CI ordered where dual independent input channels were needed — means a redesign, a return, and a delay. A related error is assuming that all Guardmaster relays carry the same output count; an engineer expecting four safety outputs from a CI unit will find three, which may require an EM expansion module that was not in the original BOM. Price sensitivity is a genuine factor in community discussions: Guardmaster hardware sits at a higher price point than some competing safety relay families, and buyers frequently raise the comparison with Pilz, Siemens, and Schneider alternatives when evaluating total project cost. For applications where the broader Rockwell ecosystem is already installed, the integration value typically justifies the premium. For standalone safety circuits on machines with no other Rockwell hardware, a cross-brand comparison is worth doing before committing.

Wiring and Installation Overview

The following points cover the key requirements and checks for installing the 440R-S13R2. Full wiring diagrams and configuration procedures are available in the Guardmaster Safety Relays user manual from Rockwell Automation — engineers specifying safety-rated installations must reference that documentation directly.

  • Confirm the control panel supply is 24 VDC and that appropriate upstream overcurrent protection is in place before wiring; the relay requires external circuit protection and contains no integrated breaker.
  • Set the input configuration method (such as DIP switches) to match the connected safety device type — N/C contact, OSSD, or supported solid-state device — before powering up; a mismatch is the primary cause of nuisance trips and failure-to-start faults at commissioning.
  • Wire the safety device to the configurable input terminals and the three safety output contacts in series with the coils of the contactors or final switching elements that remove energy from the hazard.
  • Connect the solid-state auxiliary output to a PLC input or indicator lamp if status feedback and trip logging are required; this output is not a safety-rated channel and should not substitute for a safety output in the switching circuit.
  • After wiring, perform a documented functional test — actuate the safety device, confirm all three safety outputs drop out, verify LED indicators reflect the correct states, and record results before machine handover.

Compatible Modules and GSR System Expansion

The 440R-S13R2 is designed to operate as part of the broader Guardmaster GSR family. The following modules are part of the same Bulletin 440R lineup and are relevant to system expansion planning:

  • Guardmaster EM — Expansion module that adds additional normally open safety output contacts when the three outputs of the CI relay are insufficient for the number of contactors or zones being switched.
  • Guardmaster EMD — Expansion module with delayed outputs, used when a time-delayed safety output is required alongside the CI relay's instantaneous contacts.
  • Guardmaster DI / DIS — Dual-channel contact input safety relays; linked to the CI via single-wire safety connection when additional input channels are required in the same safety circuit.
  • Guardmaster SI — Single-channel fixed-contact input relay; can be linked to the CI for circuits requiring additional fixed-input zones.
  • Guardmaster GLP — Guard locking module for solenoid-lock or trapped-key guard door applications; integrates into the same GSR single-wire safety connection topology.

Wrong-Part Prevention Checklist Before Ordering the 440R-S13R2

Before confirming your order, verify every item on this checklist against your risk assessment and wiring diagrams. These checks address the most common causes of ordering errors with the 440R-S13R2 and the broader 440R GSR family:

  1. Confirm the control supply available is 24 VDC and not 24 VAC or 120 VAC.
  2. Verify you actually need a configurable single input safety relay (CI type) rather than a dual-input or time-delay module.
  3. Check that your safety devices (E-stop, gate switch, OSSD sensor, safety mat) are supported by the CI's input types and configuration.
  4. Ensure three NO safety outputs and one auxiliary solid-state output are sufficient for the number of contactors/loads you must switch.
  5. Confirm panel space and DIN rail mounting are compatible with existing control cabinets.
  6. Verify performance level/SIL and category requirements in your risk assessment can be met using this relay and your chosen devices.
  7. Check that the single-wire safety connection feature is compatible with any existing Guardmaster GSR modules you plan to link.
  8. Verify regional certifications (CE, cULus, etc.) align with the site's regulatory requirements.

If any item on this checklist raises a question, contact the LeadTime.ca team before ordering — confirming the right part now prevents costly redesigns and delays later. You can also review the full product details at LeadTime.ca to cross-reference your requirements against the listed specifications.

Frequently Asked Questions

What is the difference between the Guardmaster CI, DI, and SI safety relays, and how do I know which one I need?

The CI (configurable input) variant — the 440R-S13R2 — accepts a single input that can be set to match N/C contact devices, OSSD sensors, or selected solid-state safety devices. The DI variant accepts dual-channel N/C contact inputs for higher redundancy with dry-contact safety devices. The SI variant accepts a single fixed N/C contact input with no input-type flexibility. If your safety device produces OSSD outputs or you need one relay to work with different device types across machine variants, the CI is the appropriate choice; if you need two independent contact-based input channels in one module, the DI is correct.

Can I wire an OSSD light curtain directly to the 440R-S13R2?

Yes — the 440R-S13R2's configurable input supports OSSD-output safety devices when the relay is set to OSSD input mode using the appropriate configuration method as described in the Guardmaster Safety Relays user manual. Wiring an OSSD device to a relay left in N/C contact mode is the most commonly reported cause of nuisance trips and failure-to-start faults; always set and verify the input configuration before functional testing.

How do I use the auxiliary solid-state output for PLC diagnostics, and is it a safety-rated output?

The auxiliary solid-state output is an informational status output — it reflects the relay's operating state (safe-to-run versus tripped) and can be wired directly to a standard PLC digital input or an indicator lamp for event logging and fault annunciation. It is not a safety-rated output and must not be used in place of the three normally open safety contacts in a safety-critical switching circuit. Use it for diagnostics, HMI indication, or PLC-based trip logging only.

Can I expand my safety circuit by linking another Guardmaster GSR module to the 440R-S13R2?

Yes — the single-wire safety connection feature is specifically designed for this purpose. It allows additional Guardmaster GSR modules to be linked to the 440R-S13R2 with a simplified wiring connection rather than running full multi-wire safety circuits between each module. Verify that the GSR module you intend to link is compatible with the single-wire safety connection topology as described in the current Guardmaster Safety Relays user manual.

How do I confirm the safety performance level or SIL achievable with the 440R-S13R2 in my specific application?

The performance level or SIL achievable in a safety circuit depends on the combination of the relay, the connected safety devices, the wiring architecture, and the test interval — not on the relay alone. Use Rockwell Automation's official SISTEMA library data or PABST calculation tool with the 440R-S13R2 safety parameters from the current datasheet to evaluate the complete safety function against EN ISO 13849 or IEC 62061 requirements. Do not rely on a single-component claim; the calculation must cover the full safety function from sensor to final switching element.

Is the 440R-S13R2 an active catalog number, and are replacement parts readily available?

The 440R-S13R2 is part of the active next-generation Guardmaster GSR lineup as documented in current Rockwell Automation literature. It is available through Rockwell-authorized distributors and safety specialists with lead times that typically range from immediate stock to several weeks depending on channel and order volume. For current availability and lead time confirmation before committing to a production build schedule, check the product page at LeadTime.ca or contact the team directly.

Why Order the 440R-S13R2 Through LeadTime.ca

  • Global shipping — LeadTime.ca sources and ships industrial automation hardware worldwide, not limited to any single region.
  • Specialist verification — Our team can cross-check your catalog number, input type, and output count against your application requirements before the order ships, reducing the risk of wrong-variant errors.
  • Hard-to-find parts — We source active, discontinued, and hard-to-locate industrial automation components including safety hardware across multiple product families.
  • Volume and project pricing — Contact us for pricing on multi-unit orders or full machine BOM requirements.
  • Response time — We respond promptly to quote requests and availability inquiries so you can confirm lead times before a build deadline.

At-a-Glance Summary

  • Catalog number: Allen-Bradley 440R-S13R2 — Guardmaster CI Safety Relay, Bulletin 440R.
  • Supply voltage: 24 VDC — no 24 VAC or 120 VAC variant under this catalog number.
  • Safety input: 1 configurable channel supporting N/C contacts, OSSD outputs, and selected solid-state safety devices.
  • Safety outputs: 3 normally open safety contacts for controlling contactors or final switching elements.
  • Auxiliary output: 1 solid-state status output for PLC diagnostics or indicator signaling — not safety-rated.
  • Mounting: DIN rail, standard control panel form factor.
  • Certifications: cULus, CE, and additional regional approvals — verify exact marks from current datasheet.
  • Safety standards: Designed for systems evaluated per EN ISO 13849, IEC 62061, and IEC 61508 — performance level and SIL ratings must be confirmed via full safety function calculation using manufacturer data.
  • Key differentiator within GSR family: Configurable single input plus single-wire safety connection for expansion.
  • Not the right fit when: Dual independent input channels, built-in time delay, guard locking, or multi-zone logic is required.
  • Availability: Active catalog number; generally stocked through Rockwell-authorized and specialist distributors worldwide — confirm live availability before build commitment.

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